Contamination prevention in C19 intubation

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This is not just about the AORN. This is about the low IQ and high Dunning-Kruger of the clipboard nurse who decides.

Look at their "thinking" in my link above:
"Is the person that is unable to wear a surgical N95 respirator critical to the procedure or can that person can be safely replaced by an equally qualified individual who can wear a surgical N95 respirator?" What do you think the answer will be to that?
Oh I agree about the clipboard warrior thing.
I was just clarifying that it is an individual hospital/ surgicenter that says no PAPRs in OR, not AORN.
 
Don't allow a PAPR for intubation of a positive patient ? What hospitals are those ?

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For intubation (in a separate room), yes. In the OR where the surgery will happen, no.
 
Oh I agree about the clipboard warrior thing.
I was just clarifying that it is an individual hospital/ surgicenter that says no PAPRs in OR, not AORN.
It IS the AORN. Read that newsletter I linked to. They argue for replacing any provider who cannot use an N95, whenever possible.

Here: 3 Interventions When Using a Powered Air-Purifying Respirator in the OR - Periop Today - AORN

We are one of the few countries where anesthesiologists have to wear masks in the OR. Why do you think that is? Uneducated *****s don't understand that "common sense" does not equal evidence in medicine (and has been proven to be incorrect later, many times).
 
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The AORN article doesn't prohibit PAPRs - it just says if they are the type with an exhaust it should not be directed at the sterile field, which makes sense.

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I hate to post this but all CRNAs/MDs should assume there will be asymptomatic patients undergoing elective surgeries. My best guess is that 1/150 patients may test negative yet still be contangious for Covid 19. Maybe in your area the correct stat is 1/200 but the number isn't zero. The younger and healthier the patient the more likely he/she could be an asymptomatic carrier.

While there will be asymptomatic carriers, the ratio greatly depends on local prevalance of the disease and sensitivity of the test. I think I read the PCR tests have like 98-99% sensitivity. Even if you had a 20% prevalence in the community, a 99% sensitive test would mean only something like 1/500 negative tests is a false negative (1/5 patients actually positive, 1/100 positive patients tests negative). You would need a 50% prevalence rate in your community with a 99% sensitive test to see even 1/200 patients be truly positive despite a negative test.

(i confess to it having been a long time since I did statistics)
 
While there will be asymptomatic carriers, the ratio greatly depends on local prevalance of the disease and sensitivity of the test. I think I read the PCR tests have like 98-99% sensitivity. Even if you had a 20% prevalence in the community, a 99% sensitive test would mean only something like 1/500 negative tests is a false negative (1/5 patients actually positive, 1/100 positive patients tests negative). You would need a 50% prevalence rate in your community with a 99% sensitive test to see even 1/200 patients be truly positive despite a negative test.

(i confess to it having been a long time since I did statistics)
You're missing one thing: the PCR test may be 99% sensitive once you get the CORRECT samples, but, including the sampling error (very high, because the virus is not always present in upper respiratory secretions), it's less than 70% sensitive. So the FNR is closer to 30%.

Let's assume you have your 20% prevalence. So, out of 1000 patients, 200 will be infected. If you test the 1000, with a FNR of 30%, you will have 60 of those 200 falsely negative, and 140 TP. So you will have 800 TN and 60 FN, meaning that only 1 in 13-14 negative patients will be a false negative. Still pretty good odds that a negative is a true negative.

At 50% prevalence, it's 500 TN and 150 FN, so it's about 1 in 4.
 
While there will be asymptomatic carriers, the ratio greatly depends on local prevalance of the disease and sensitivity of the test. I think I read the PCR tests have like 98-99% sensitivity. Even if you had a 20% prevalence in the community, a 99% sensitive test would mean only something like 1/500 negative tests is a false negative (1/5 patients actually positive, 1/100 positive patients tests negative). You would need a 50% prevalence rate in your community with a 99% sensitive test to see even 1/200 patients be truly positive despite a negative test.

(i confess to it having been a long time since I did statistics)
You're missing one thing: the PCR test may be 99% sensitive once you get the CORRECT samples, but, including the sampling error (very high, because the virus is not always present in upper respiratory secretions), it's less than 70% sensitive. So the FNR is closer to 30%.

Let's assume you have your 20% prevalence. So, out of 1000 patients, 200 will be infected. If you test the 1000, with a FNR of 30%, you will have 60 of those 200 falsely negative, and 140 TP. So you will have 800 TN and 60 FN, meaning that only 1 in 13-14 negative patients will be a false negative. Still pretty good odds that a negative is a true negative.

At 50% prevalence, it's 500 TN and 150 FN, so it's about 1 in 4.


There are 2 sets of numbers. Analytic sensitivity and specificity are not the same as clinical sensitivity and specificity.

 
ETT vs. LMA: which generates more aerosol ?

Paralysis makes a difference as LMA is inserted in a spontaneously breathing patient, whereas the patient is only breathing spontaneously during extubation.
LMA often requires manipulation to optimize it's position and the seal is not as good as with an ETT. Positive pressure is sometimes needed.

Likely Conclusion:

ETT intubation generates less aerosol (paralysis).

LMA generates more aerosol during surgery.

Extubation generates equivalent amount of aerosol.p



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the person is apneic when you put the LMA in thus no air is moving (whether you use paralytics or not is irrelevant)

If you have a covid negative person with no symptoms, breathing spontaneously through an average LMA, the idea that:

1. the person is really covid positive AND
2. the LMA seal is so crappy that airway gases are spilling out into the room at a clinically relevant rate AND
3. those gases are going to get through my PPE

- I just dont buy it. I think that intubating this person for no other reason than containing this theoretical LMA leak will indefinitely lead to more coughing, bucking, need for close contact with the airway after the case in some cases..

when you put the LMA in and it goes smooth (which is HIGHLY likely) it takes literally 2 seconds, you are not really close with your face to the airway, and you just change your gloves after..
 
the person is apneic when you put the LMA in thus no air is moving (whether you use paralytics or not is irrelevant)

If you have a covid negative person with no symptoms, breathing spontaneously through an average LMA, the idea that:

1. the person is really covid positive AND
2. the LMA seal is so crappy that airway gases are spilling out into the room at a clinically relevant rate AND
3. those gases are going to get through my PPE

- I just dont buy it. I think that intubating this person for no other reason than containing this theoretical LMA leak will indefinitely lead to more coughing, bucking, need for close contact with the airway after the case in some cases..

when you put the LMA in and it goes smooth (which is HIGHLY likely) it takes literally 2 seconds, you are not really close with your face to the airway, and you just change your gloves after..
The only argument is that, after extubation, one leaves the room soon, instead of sharing the contaminated air for a while (until it's filtered out of the room).

I would definitely use an ETT in a Covid+ person, but intubate/extubate in a separate (negative pressure) room.

Also, there is a big difference between somebody with hundreds/thousands of LMAs placed, and the occasional dabbler in LMAs.
 
This is not just about the AORN. This is about the low IQ and high Dunning-Kruger of the clipboard nurse who decides.

Look at the recommended "thought" process in my link above:
"Is the person that is unable to wear a surgical N95 respirator critical to the procedure or can that person can be safely replaced by an equally qualified individual who can wear a surgical N95 respirator?" What do you think the answer to that will be?
Excellent Dunning-Kruger reference.
 
Apnea during LMA insertion:

Yes after 2 mg/lb of Propofol most people will be apneic. During a Sevo inhalational induction patients mostly still breathe. If u get apnea u have to use PPV which a lot of times then leaks around the LMA cuff.

A 2 sec LMA insertion:

that is *the best case scenario*: a good number of times one has to reposition the LMA (let's be honest) while one NEVER has to reposition an ETT.

An ETT seal is no doubt better than an LMA.

It is true one has to be experienced, an artist and lucky all at the same time not to ever have any leak or use PPV with an LMA. I may not be as good as some others but i have used LMAs for 30 yrs (England) and I still get leaks - just yesterday and also today, that's why I am honestly writing about it.

In other words in the theoretical world LMAs could be as good as ETTs in preventing aerosol leaks but in the real world unfortunately and as much as we would like them to be they are not.
Let's just admit it...
There also is contact contamination during the repostitioning, LMA size change etc...and...please don't say u never have to change the LMA size ...


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Apnea during LMA insertion:

Yes after 2 mg/lb of Propofol most people will be apneic. During a Sevo inhalational induction patients mostly still breathe. If u get apnea u have to use PPV which a lot of times then leaks around the LMA cuff.

A 2 sec LMA insertion:

that is *the best case scenario*: a good number of times one has to reposition the LMA (let's be honest) while one NEVER has to reposition an ETT.

An ETT seal is no doubt better than an LMA.

It is true one has to be experienced, an artist and lucky all at the same time not to ever have any leak or use PPV with an LMA. I may not be as good as some others but i have used LMAs for 30 yrs (England) and I still get leaks - just yesterday and also today, that's why I am honestly writing about it.

In other words in the theoretical world LMAs could be as good as ETTs in preventing aerosol leaks but in the real world unfortunately and as much as we would like them to be they are not.
Let's just admit it...
There also is contact contamination during the repostitioning, LMA size change etc...and...please don't say u never have to change the LMA size ...


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How are you practicing in England, yet you are talking about 2mg/lb?
We don’t even dose like that in the US, as much as we try to be different.
What is the deal?
 
So, is anyone else encountering nonsensical demands from hospital admin to wear full airborne precautions PPE throughout cardiac cases (in negative patients), just because there is a TEE probe in place? They are citing recommendations from ASE and SCA that TEE is an aerosol-generating procedure, even with an ETT and general anesthesia, and are thus requiring full precautions, for everyone in the room, for the entirety of the case. I find it ridiculous, and counter to actual physics and common sense. In their recommendations, the authors at the ASE/SCA note that it is "generally accepted" that TEE warrants airborne precautions, regardless of whether or not a patient is intubated, but fail to provide any source to back up that assertion. A TEE probe in the esophagus of an intubated patient cannot generate airflow necessary to aerosolize particles and lead to an increased infectious risk. Virus on the probe itself can be infectious, but that's what gloves are for, not PAPR. Following this recommendation will lead to even faster depletion of already low resources in the hospital with no benefit to the OR staff.
We’re getting the “don’t use the Bair hugger” BS.
 
Did u not know that ? For Propofol it's just easier to calculate because it comes out to 1mg/lb so like 200 mg/200 lbs which turns out to be the suggested mg dose. Hey...i still have something I can give to the world...

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Did u not know that ? For Propofol it's just easier to calculate because it comes out to 1mg/lb so like 200 mg/200 lbs which turns out to be the suggested mg dose. Hey...i still have something I can give to the world...

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So you guys use lbs in England? That was really my question. Or are you no longer there?
I thought the rest of the world used kg. And you guys have this stone thing.
 
Anesthesiologists and intensivists in the UK not among the deceased among healtcare workers:


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